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Conservation practice construction specifications are reviewed periodically, and updated if needed.To obtain the current version

of this specification, contact the Natural Resource ConservationService.

NATURAL RESOURCES CONSERVATION SERVICE

CONSERVATION PRACTICECONSTRUCTIONSPECIFICATION

IRRIGATION PIPELINE

STEELPIPELINE

CODE 430SP

1.

SCOPE

The work shall consist offurnishing andinstallingsteel pipe

and necessary appurtenances, linings,and coatings to the alignment, grades, and dimensions as shownon the drawings. The work alsoincludes site preparation, earth fill, and excavation. Unless otherwise specified, the pipe shall conformto the requirements listed in this specification, NRCS Standard 430, and the requirements shown onthe drawings.

Standard Specification for Threaded Couplings, Steel, Black or Zinc-Coated(Galvanized) Welded or Seamless, for Use in Steel Pipe Joints

ASTMB418

Standard Specification for Cast and Wrought Galvanic Zinc Anodes

American Water Works Association (AWWA)

AWWA C200

Steel Water Pipe--6 In.and Larger

AWWA C203

Standard for Coal-Tar Protective Coatings and Linings for Steel Water Pipelines—Enamel and Tape—Hot Applied

AWWA C206

Standard for Field Welding of Steel Water Pipe

AWWA C207

Standard for Steel Pipe Flanges for Waterworks Service-

Sizes 4 In. Through 144 In.

AWWA C209

Standard for Cold-Applied Tape Coatings for the Exterior of Special Sections,Connections, and Fittings for Steel Water Pipelines

Construction Specification 430SP-2

NRCS, NM

June 2011

AWWA C210

Standard for Liquid-Epoxy Coating Systems for the Interior and Exterior of SteelWater Pipelines

AWWA C213

Standard for Fusion-Bonded Epoxy Coating for the Interior and Exterior of Steel WaterPipelines

AWWA C214

Standard for Tape Coating Systems for the Exterior of SteelWater Pipelines

AWWA C218

AWWA Standard for Liquid Coating Systems for the Exterior of Aboveground SteelWater Pipelines and Fittings

AWWA C222

Standard for Polyurethane Coatings for the Interior and Exterior of Steel Water Pipeand Fittings

AWWA C606

Standard for Grooved and Shouldered Joints

3.

HANDLING AND STORAGE

Pipe shall bebraced as required to maintainitsroundness

when stored

and handled.

Coated pipe shall be stored on padded skids,

tires, or other suitable means so that coating will not bedamaged.

Pipe shall also be piled and blocked with strips between tiers.

Coated pipe shall be handled with wide belt slings, padded forks, or other means that will not damagethe pipe. Chains, cables, or other equipment likely to cause damage to the pipe or coating shall notbe used.

Pipe shall not be rolled or dragged on the ground.

Each section of pipe shall be delivered in the field as near as practicable to the place where it is to beinstalled.

If the pipe is supported, as for welding, supports shall be of sufficient width and number and bepadded, as

necessary, to prevent damage to the coating.

Pipe shall be visually inspected for damage to the coating. Any damaged areas shall be repaired inaccordancewith the standard to whichthe original

coating was applied

and section 5 part E of thisspecification.

4.

MATERIALS

a.

Pipe

Requirements.Steel pipe shall conform to the requirements of the applicable specificationlisted below for the kind of pipe and the type, weight, grade, and finishasspecified

in the drawings:

i.

ASTM A53

ii.

ASTM A134

iii.

ASTM A135

iv.

ASTM A139

v.

AWWA C200

b. Coating and Liningfor Pipes.Coating and lining materials shall conform to the applicablespecification as detailed

Field coating and lining shall conform to the applicable standard listed aboveand section 5 part E

of this specification.

c. Fittings.Fittings shall be fabricated in accordance with one of the following applicablespecifications:

i.

ASTMA858–

for low-temperature and corrosive service

ii.

ASTM A865–

threading couplings

iii.

AWWA C200 Section 4

Fittings may be fabricated into standard or special pipelengths.

All fittings shall be of the samematerial grade, strength and dimensions as the pipe.

d. Joints and Connections.Pipe joints shall conform to the details shown on the drawings and shallbe sound and watertight at the pressures specified in this specification or as may be shown on thedrawings.

i.

Welded Joints.Welding and welded joints shall conform to the welding procedure detailsand requirements of AWWA Standard C206. Field welding shall be done in such a way asto avoid burning the protective coating on the pipe except in the immediate vicinity of theweld.

Where welded field joints are used, they shall be single welded butt joints or lapwelded slip joints, as shown on the drawings. Special closure lap joints shall be used asdescribed inAWWA Standard C206.

ii.

Gasketed Joints.Gasketed jointsand gasketsshall conform to AWWA C200.Thedimensions of bells and spigots shall be in accordance with the manufacturer's standarddesign dimensions and tolerances.

The pipe shall be laid with the bell

oriented upstream.The spigot end shall be seated in the bell to a depth as recommended by themanufacturer. The spigot, when seated, shall compress the gasket radially in its annularrecess to provide a positive seal. Joints with fish-mouthed gaskets will be taken apart andreseated with a new gasket.

iii.

Mechanical Couplings.The ends of pipe to be connected with mechanical couplings shallbe machinedto allow coupling the pipe sections without damaging or displacing thegaskets and to ensure uniform end separation of the pipes. Machined ends of the pipe thatreceive the coupling sleeves shall be free from dents, gouges, rust, or scale. The pipe andConstruction Specification 430SP-4

NRCS, NM

June 2011

couplings shall be assembled with continuous rubber ring gaskets conforming to thedimensions and tolerances recommended by the pipe manufacturer. Coupling followersshall be drawn up evenly to ensure uniform pressure on the gaskets.

Grooved andshoulderedjoints shall be furnished and installed in accordance with AWWA StandardC606.

iv.

Flanges.

All steel ring flanges and gasketsshall be fabricated in accordance with AWWAStandard C207. Gaskets shall be either a neoprene cloth insert 1/16 or 1/8 inch thick

or redrubber 1/16 inch thick.The gasket shall be full face where used between flat face flangesurfaces.

conforming to AWWA C203,epoxy paintconforming to AWWA C210 or C 213, or as recommended by pipe manufacturer. Bolts and nuts shallbe type 316 stainless steel andshall be field coated with a coal tar enamel orepoxy enamel.

f.Corrosion Protection

i.

Anodes.

Zinc anodes shall meet or exceed the requirements of ASTM

Specification B418.

Each anode shall have a solidly attached full-length core with a single strand of insulatedcopper wire. The wire shall be 12 gageor larger. If a header wire is used, the gage shallbe adequate to catty the design current with

no more than a 20 mV I-R drop.

All anodesshall be commercially packaged.

ii.

Welding Electrodes.Steel welding electrodes shall conform to the requirements ofAmerican Welding Society Specification AWS A5.1, "Specification for Mild Steel CoveredArc-Welding Electrodes," except that they shall be uniformly and heavily coated (notwashed) and shall be of such a nature that the coating does not chip or peel while beingused with the maximum amperage specified by the manufacturer.

5.

INSTALLATION

Constructionactivities shall follow all OSHA standards and regulations. All work shall be neat and of aprofessional quality.

a. Site preparation and earthwork.

Site preparation, foundation work, and earthwork

shall be inaccordance with NM NRCS Construction Specification 587.

b. Buried pipeline.

i.

Minimum depth of cover.Pipe shall be installed at sufficient depth below the groundsurface to provide protection from hazards imposed by traffic crossing, farming

operations,freezing temperatures, or soil cracking. The minimum depth of the cover shall be 24inches.

ii.

If necessary

to install the pipe at a shallower

depth, adequate protection shall be providedsuch as using extra heavy gauge pipe, constructing a fenceor other surface barrier aroundthe trench, or creating a bench over

pipe. The top width of the bench fill shall be no lessthan 10

feet and side slopes no steeper than 6H:1V.

iii.

Trench construction.

The minimum width of the trench shall be wide enough to permit thepipe to be easily placed and joined and to allow the initial backfill material to be uniformlyplaced and compacted under the haunches and along the side of the pipe. The maximumtrench width shall be 36 inches greater than the diameter of the pipe. If the trench isprecision excavated and has a semicircular bottom that fits the pipe, the width shall notexceed the outside diameter of the pipe by more than 10 percent.

Construction Specification 430SP-5

NRCS, NM

June 2011

iv.

The trench bottom shall be uniform so that the pipe lies on the bottom without bridging.Clods, rocks, and uneven spots that can damage the pipe or cause non-uniform supportshall be removed.

v.

If rocks, boulders, or any other materials that can damage the pipeor coatingareencountered, the trench bottom shall be undercut a minimum of 4

conditions where unstable soil, trenchdepth, or other conditions can be hazardous to personnel working in the trench.

vii.

Placement.

Inspect each pipe and fitting before lowering the pipe or fittings into the trench.Inspect the interior and exterior protective coatings. Patch damaged areas in the field withmaterial compatible with the original.

viii.

Anode installation.

Buried

pipelines shall be protected with sacrificial galvanic anodes ifthey are specified or otherwise show on the drawings.

ix.

Anodes shallbe placed as shown on the drawings.If horizontally placed, anodes shall beat or below the bottom elevation of the pipeline.Vertically placed anodes shall have aminimum distance to 3 feet between the ground surface and the top of the anode.

Anodesshall

not be placed in fill areas, and magnesium anodes must be placed a minimumdistance of 10 feet from the pipeline.

x.

Anodes shall be bedded in moist fine clay,clay loam, silt, or silt loam.In sandy andgravelly areas, fine material must be imported for bedding and for covering the anodes to adepth of 6 inches. The packaged anodes and the fine textured soil used for bedding andbackfill shall be thoroughly wetted.

xi.

The lead wire from the anode

or the header wire for multiple anode installations

shall beattached to the pipeline by cadwelding, thermowelding, orothersimilarprocesses.Testingstation facilities shall be located and installed as specified for the job or as shown on thedrawings, or both,Wires at testing stations shall be attached to the pipe by one of theprocesses specified for anode lead wires.

c. Above ground pipelines.Concrete, timber, or other pipe supports, and anchors and thrust blocksshall be constructed at the locations to the dimensions shown on the drawingsand/or as staked in

thefield.

Saddles shall be shaped tofirmly supportthe pipe throughout the full arc of contact.At least twolayers of felt strips shall be placed between the pipe and its support unless otherwise detailed on thedrawings.

The felt shall cover theentire area of contact between the pipe and the saddle. A graphitelubricant shall be placed between the felt strips before the pipe is placed in the saddle.

Steel supports and saddles shall be constructed of material that equals or exceeds the requirementsspecified in ASTM

A36.

All exposed steel shall be coated as described in section 4 partb.ii

and section 5

parte

of thisspecification.

d.On ground pipelines.Pipe shall belaid to the lines and grades as shown on the drawings and/oras staked in the field. Pipe shall be protected from the hazards imposed by traffic crossings, farmoperations, or other hazards.

The ground shall be shaped

to provideuniform support to the pipe. Ifrocks or objects that might damage the pipe coating

are present, sand

or soil shall be used as a basefor the pipe.

Concrete, timber, or other anchors and thrust blocks shall be constructed at the locationsto the dimensions shown on the drawings and/or as staked in the field.

Construction Specification 430SP-6

NRCS, NM

June 2011

e.Field lining, coating and repair.Field lining coating and repair of field joints,connections

andappurtenances

shall be completed in accordance with the standard to which the original coating

wasapplied, unless otherwise specified in the drawings.

i.

Surface preparation.Bare steel surfaces shall be prepared for coating by removing allgrease and oil or other soluble contaminants with solvent commercial cleaners (wiping,dipping, or steam) or vapor degreasing. After degreasing, surfaces shall be cleaned withhand tools to remove all loose scale rust and other loose detrimental foreign matter.

ii.

On previously coated surfaces, all dirt, paper, and other foreign matter and loose coatingshall be removed. Kraft paper, whitewash, or other surface protective layers shall beremoved at least 12inches on either side of the bare steel to be coated.

shall bethoroughly mixed and applied in strict adherence to manufacturer's instructions.The primershall be permitted to dry to the consistency recommended by the manufacturer beforeapplying the coating.

v.

No foreign matter shallencounter

the primed surface before application of the coating.

vi.

Application of primer to surfaces shall be limited to that amount of area that can be finishedduring the same work shift.

After assembly, all pipe joints shall be field wrapped inaccordance with AWWA C209 or AWWA C214, as appropriate.

A tape or filler tape shall be cigarette wrapped over the annular ring of the joint.The pipe coating shall be primed 2 inches back from the coating cutback and twolayers of tape shall be wrapped overlapping 2 inches of pipe coating on one sideof the joint, extending across the joint and overlapping 2 inches of coatingon theother side of the joint.

Coal tar enamel coating cutback edges shall be tapered back until 1 inch of coaltar is exposed on the taper before priming and wrapping. Wraps shall beterminated on the underside of the pipe. Tape widths shall be 6 inches for pipegreater than 8 inches in diameter and 4 inches for pipe 2 to 8 inches in diameter.

f. Trenchless pipe installation.Auger and drying boring, pipe jacking, or other trenchlesspipeinstallations shall be designed by the engineer and shall be approved prior to commencement ofconstruction.

6.

QUALITY ASSURANCE

a. Testing.

Underground

pipelines shall be tested before placing the backfill over the field joints.Abovegroundpipelines

may be tested at any time after installation and prior to operation.

The pipeline shall be filled with water, taking care to bleed air and prevent water hammer.When theline is full, all valves shall be closed, and the line

shall be brought up to full design working pressure.All joints shall then be carefully inspected for leakage and any visible leaks shall be repaired.

operated at design capacity. Objectionable surge, water hammer, unsteady delivery of water,damage to the pipeline, and detrimental discharge from control valves are evidence of malfunction.

b. Quality checks andguarantee.The contractor shall contact the local NRCS office at least 24hours in advance of any pipe that will be buried for quality assurance checks relating to pipe gradeand appurtenances, bedding conditions, and suitableness of backfill material. Pipe andappurtenances that are of questionable quality shall be subject to rejection at NRCS discretion.

The manufacturer or supplier of pipe materials shall supply a statement certifying that all pipe andmaterials have met the standards and specifications as described in this specification, as applicable.

The installing contractor shall certify that his or her installation complies with the requirements of thisspecification and NRCS Standard 430. He/she shall furnish a written guarantee that protects theowner against defective workmanship and materials for not less than 1 year.

If requested by the state conservation engineer, a qualified testing laboratory shall certify withsupporting test results that the pipe meets the requirements in this specification.

The

acceptability of the pipeline shall be determined by inspections to check compliance with all theprovisions of this standard with respect to the design of the line, the pipe and pipe markings, theappurtenances, and the minimum installation requirements.

7.

MEASUREMENT

The quantity of each size and type of pipe shall be determined to the nearest foot by measurement ofthe laid length of pipe along the crown centerline of the pipe.

Construction Specification 430SP-8

NRCS, NM

June 2011

Project Name:

Date:

8. ITEMS OF WORK AND CONSTRUCTION DETAILS:

Items of work to be prepared in conformance with this specification and the construction details are: